The Lean Experiments Catalog — The Product Playbook

A lean experiment is a small, cheap test of one slice of your idea, run before you build the real thing. The Lean Experiments overview covered why you run them. This page is the index: a one-line description of each experiment, and a link to its own page. Click through and you get the full recipe there, what it is, when to reach for it, and a worked example to copy the shape of. The taxonomy comes from David Bland and Alex Osterwalder's Testing Business Ideas, which catalogs 44 of these tests. What follows is a curated slice, the 13 you'll reach for most, grouped by the job they do.

How this list is organized

Which experiment you reach for depends on the question you're actually asking, desirability, usability, feasibility, or messaging. The Lean Experiments overview walks through how to pick the right one; this page is the menu it points you to. Two things to know about the order below. Feasibility is an engineering question you answer with spikes and technical prototypes, a different family of tools, so you won't find feasibility experiments here. And the 13 are grouped by the job they do, then sorted cheapest-first, so read each group as a ladder: start on the cheapest rung and climb only as far as your question forces you to.

Demand signals: will anyone reach for it?

These five answer desirability, the question you start with. Anyone can get excited about building a thing; evidence that a stranger wants it is the rare part. All five are cheap, most need no engineering at all.

Landing-page test. One page that sells the product as if it already exists, with a button that records who meant it. No product behind it yet.
Fake-door test. A real-looking button for a feature that doesn't exist yet, dropped inside a product you already have. The click is the signal.
Smoke test (explainer video). A short video showing the whole product working as if it were real, published to see who signs up off the demonstration alone. Dropbox is the famous one.
Social-media teaser. A post or paid ad for the not-yet-real thing, aimed at the audience you believe wants it. Tests demand and messaging together.
Online ad test. Paid ads where you vary one thing, the headline, the image, the audience, and let the spend tell you what pulls.

Raise the cost of the yes: will the interest survive a real cost?

A click is cheap. People click out of mild curiosity and forget five seconds later. These five raise the cost of saying yes, because the harder it is to give the signal, the more it's worth. Climb here once the cheap demand signals came back positive. (One exception lives in this group: the A/B test is an optimization tool, not a higher-cost demand signal. It's here as the tuning rung you reach once a yes is already coming in.)

Concierge. You deliver the service by hand, in the open, for a handful of users who know a human is doing it, to learn whether it's worth automating before you build the machine.
Wizard of Oz. The product looks finished and automated, but behind the curtain a human is doing the work by hand, and the user thinks it's the software.
Pre-sell. You sell the thing before it exists and take real money for it, the highest-confidence demand signal there is, because money is the currency hardest to fake.
A/B test. Two versions of one thing shown to two comparable groups at once, where only a single element differs. Reach for it after demand is already proven, to push the yes-rate higher: two checkout buttons, same flow, see which one gets more clicks.
Letter of intent. A signed, non-binding document where a business customer states they intend to buy if you build what you described. The B2B answer to "will they spend."

Prototype as experiment: can they use it, does the story land?

These three ask whether a person can actually use the thing, and whether the story lands. You build a stand-in, put it in front of someone, and watch where they stumble. Start with paper, move to pixels only when paper can't answer the question. The first two test usability, the storyboard tests messaging.

Paper prototype. A paper sketch of the app. Hand the drawn screens to someone, give them a task, and watch where they pause. You're measuring friction.
Clickable (digital) prototype. The same usability test as paper, with linked digital screens, for a finer read on exactly where fingers go on a real device.
Storyboard. The customer's whole journey drawn out frame by frame. You walk a real person through it, watch where they stop nodding, and learn whether the story of how this fits their life lands.

Where to start

Start low-fidelity. Add fidelity only when you need more specific feedback. A paper sketch before a clickable one, a teaser before a landing page, a fake door before a Wizard of Oz. Every rung up the ladder costs more, so only climb when the question forces you to.

Thirteen is enough to run almost anything you'll face. When it isn't, the other 31 are in Testing Business Ideas by David Bland and Alex Osterwalder, all 44 mapped by the evidence each one buys you. But most of the time the experiment you need is already on this shelf. Pick the question, pull the recipe, go run it.